1. Field of the Invention
The present invention relates to a carrier structure for stacked-type semiconductor devices, a method of producing the carrier structure, and a method of fabricating a stacked-type semiconductor device, and more particularly, to a carrier structure for a stacked-type semiconductor device having semiconductor packages stacked and packaged into a single semiconductor package, a method of producing this type of carrier structure, and a method of fabricating the stacked-type semiconductor device.
2. Description of the Related Art
Recently, portable electronic equipment such as a movable phone, and non-volatile recording media such as IC memory cards have been downsized, and it has been required to reduce the number of components used in the apparatuses and recording media and achieve further downsizing of the components.
It is thus desired to develop the technique of effectively packaging semiconductor chips, which are essential components among the structural components. Examples of semiconductor packages that meet the requirements are a chip scale package (CSP) having a size as large as the semiconductor chips, a multi-chip package (MCP) having multiple semiconductor chips accommodated into a single package, and a package-on-package (PoP) having multiple semiconductor packages stacked and packaged into a single piece.
However, the carriers used for fabricating the stacked-type packages are required to stack the upper and lower semiconductor packages with high precision and have a certain production precision for maintaining a satisfactory production yield of the semiconductor packages.
More specifically, the carriers should be designed taking the following into consideration:
(1) the difference in dimensions between the upper and lower semiconductor packages;
(2) the difference in dimensions between the openings of the upper and lower carriers for accommodating the semiconductor packages; and
(3) the degree of self-alignment of solder balls by reflow heating after the upper and lower packages are mounted. Recent stacked-type packages have a thin total thickness, and there is an increased difficulty in producing the carriers.